Investigators comb a Central Islip house where three bodies were found by crew responding to a fire. (Aug. 11, 2009) (Credit: James Carbone)

A forensic scientist told jurors Monday that he didn't test every bloodstain for DNA from the burned-out Central Islip house where three people were tortured and killed, and that there was no need to do so. Daniel Cheswick of the Suffolk County Crime Laboratory also testified that although some evidence from the crime scene sat in a police warehouse for two years before it was analyzed, it's doubtful...

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A forensic scientist told jurors Monday that he didn't test every bloodstain for DNA from the burned-out Central Islip house where three people were tortured and killed, and that there was no need to do so.

Daniel Cheswick of the Suffolk County Crime Laboratory also testified that although some evidence from the crime scene sat in a police warehouse for two years before it was analyzed, it's doubtful DNA degraded in that time.

Cheswick finished three weeks of testimony Monday before Suffolk County Court Judge James Hudson at the trial of Hasan Vaughan and Thomas Singletary, both 36 and of Central Islip. They are charged with first-degree murder and arson in the August 2009 deaths of Louis Calixto Jr., 19; his friend, Mykier Daniels, 28; and her sister, Katrice Daniels, 31.

During cross-examination by Singletary's attorney, Daniel Russo, Cheswick said he got DNA from two bloodstains on the side-door jamb but didn't test a third. Similarly, he didn't test other stains from the door and a screen door nearby.

During questioning by Assistant District Attorney Robert Biancavilla, Cheswick said there was no need to test every stain when a "representative sample" would do. He found that a piece of charred skin stuck to a door and blood leading from the bodies to the home's exit belonged to the defendants.

Russo again questioned the crime lab's control of evidence it collected, a topic frequently raised by the defense in the trial. Much of the evidence was out of the lab's hands for two years while it sat in the police department's property bureau in Yaphank.

Cheswick said more than a dozen items from the crime scene came back for testing to the lab after two years, but testing did not recover any DNA from those items, which included a door knob found on Katrice Daniels' body, a knife and keys found in the room with the bodies.

"DNA does degrade," Cheswick told Russo.

But later, he told Biancavilla that if it's kept dry, it can last decades without refrigeration. He said his inability to find DNA on those items does not necessarily mean it degraded while in the police warehouse.

"It's possible it was never there," he said.

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